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9

If this were SO I would say notepad++. But, alas, I am at a loss.
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jjnguyApr 30 '09 at 9:48

7

A good text editor is critical for server admin too I think
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Glenn SlavenApr 30 '09 at 10:18

13

Wish that people would add items individually to a question like this because otherwise everyone posts huge lists which everyone eventually just gives up reading.
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Rory BeckerApr 30 '09 at 12:22

Beyond Compare is one of the applications I'd want to have with my if I were stranded on a desert island. Er, with a computer.
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dthrasherApr 30 '09 at 13:08

1

Is that still shareware? I propose WinMerge, which is freeware...
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alexJun 3 '09 at 21:01

2

It's worth buying and does a lot more than winmerge - I use it to test failed file transfers of large trees, but it can even go as far as showing you what's different in photos
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reconbotOct 15 '09 at 18:49

In top of that, I strongly recommend to add TrueCrypt if you keep any personal or confidential data. Sometimes I need to put customer's database backups and I'd be in great trouble if someone gets access to them.

Notepad++ - this is one of my favorite text editors – now made portable

Color Cop – this is one of my favorite freeware apps – includes an eyedropper you can drag over any window to grab the color value. It then offers a palette of 42 complimentary colors to the one you've picked.

Ifranview – a light little graphics viewer/editor that packs a big punch. You can use it to work with screen captures, create slideshows and more

GIMP – the popular open source image editor packaged as a portable app – very robust

Roeder's .NET Reflector – recently purchased by Red Gate, this still-free app can be used to explore .NET assemblies, understand relationships between classes and methods, find where types are instantiated and exposed or check that code has been correctly obfuscated before release. There are also over 30 add-ins available.

Process Explorer – formerly Filemon and Regmon, this is an invaluable sleuthing tool

TightVNC – based on the popular VNC remote control software, this version can live on a thumb drive

WinMerge – compares differences between files and merges changes. It has the same features as the desktop version

Portable Apps Suite – this is the mac-daddy of them all – it includes Firefox, Thunderbird(email), Sunbird(calendar),ClamWin (antivirus), Pidgin(see above), Sumatra PDF Readable, KeePass Password Safe, OpenOffice, CoolPlayer (audio Player) and even a couple of games

Restoration – Recover accidentally deleted files – even after they were deleted from the recycle bin

[Update: Initially I deleted this answer because I spotted it was already mentioned in the question. However I think it would be good for it to see votes so I have checked the Community Wiki box to prevent people from thinking I'm trying to game the system]

Linux (e.g. Debian, Knoppix, Puppy). Even if the systems you're working with aren't Linux, you can get useful things done by having a full, working OS in your pocket; sometimes having a different OS can even be an advantage.

A ton of sysadmin work is done at the command line, and deals with log files. Finding that needle in the haystack in minutes while other admins take hours gives you a significant edge in solving a critical issue.
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Adam DavisApr 30 '09 at 17:08

The main reason being that when you work with governmental organizations, you can't always get access to the Internet, but (for me) it was easy to burn CDs there. It made debugging bad hardware, and problemtic OSs much easier.

Definitely Total Commander. Just runs out of the install folder; does packing/unpacking, FTP, file diff, folder sync, multi-rename, checksum generation/verification. You name it...

For those who still own POP3 accounts; E-Res-Q (shameless plug!) allows no-frills access to a POP3 account for quick viewing and cleanup of messages (good for clearing spammed out or blocked-with-a-50MB-attachment accounts).

The Computer Repair Utility Kit that Technibble put together has most of the essential tools you'd need. It's been designed so that the tools can run from a USB drive. Unfortunately, they no longer distribute the toolkit themselves, but you can probably find a copy elsewhere.